qapi: Fix detection of doc / expression mismatch

This fixes the errors uncovered by the previous commit.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-32-git-send-email-armbru@redhat.com>

scripts/qapi.py

@@ -248,18 +248,21 @@ class QAPISchemaParser(object):
         self.line_pos = 0
         self.exprs = []
         self.docs = []
+        self.cur_doc = None
         self.accept()
 
         while self.tok is not None:
             info = {'file': fname, 'line': self.line,
                     'parent': self.incl_info}
             if self.tok == '#':
-                doc = self.get_doc(info)
-                self.docs.append(doc)
+                self.reject_expr_doc()
+                self.cur_doc = self.get_doc(info)
+                self.docs.append(self.cur_doc)
                 continue
 
             expr = self.get_expr(False)
             if 'include' in expr:
+                self.reject_expr_doc()
                 if len(expr) != 1:
                     raise QAPISemError(info, "Invalid 'include' directive")
                 include = expr['include']
@@ -269,6 +272,7 @@ class QAPISchemaParser(object):
                 self._include(include, info, os.path.dirname(abs_fname),
                               previously_included)
             elif "pragma" in expr:
+                self.reject_expr_doc()
                 if len(expr) != 1:
                     raise QAPISemError(info, "Invalid 'pragma' directive")
                 pragma = expr['pragma']
@@ -280,13 +284,23 @@ class QAPISchemaParser(object):
             else:
                 expr_elem = {'expr': expr,
                              'info': info}
-                if (self.docs
-                        and self.docs[-1].info['file'] == fname
-                        and not self.docs[-1].expr):
-                    self.docs[-1].expr = expr
-                    expr_elem['doc'] = self.docs[-1]
-
+                if self.cur_doc:
+                    if not self.cur_doc.symbol:
+                        raise QAPISemError(
+                            self.cur_doc.info,
+                            "Expression documentation required")
+                    self.cur_doc.expr = expr
+                    expr_elem['doc'] = self.cur_doc
                 self.exprs.append(expr_elem)
+            self.cur_doc = None
+        self.reject_expr_doc()
+
+    def reject_expr_doc(self):
+        if self.cur_doc and self.cur_doc.symbol:
+            raise QAPISemError(
+                self.cur_doc.info,
+                "Documentation for '%s' is not followed by the definition"
+                % self.cur_doc.symbol)
 
     def _include(self, include, info, base_dir, previously_included):
         incl_abs_fname = os.path.join(base_dir, include)
@@ -950,11 +964,6 @@ def check_exprs(exprs):
 
 
 def check_freeform_doc(doc):
-    if doc.symbol:
-        raise QAPISemError(doc.info,
-                           "Documention for '%s' is not followed"
-                           " by the definition" % doc.symbol)
-
     body = str(doc.body)
     if re.search(r'@\S+:', body, re.MULTILINE):
         raise QAPISemError(doc.info,

tests/qapi-schema/doc-before-include.err

+tests/qapi-schema/doc-before-include.json:3: Documentation for 'foo' is not followed by the definition

tests/qapi-schema/doc-before-include.exit

-0
+1

tests/qapi-schema/doc-before-include.json

 # Doc comment separated from defining expression by non-defining expression
-# BUG: not rejected
 
 ##
 # @foo:

tests/qapi-schema/doc-before-include.out

-enum QType ['none', 'qnull', 'qint', 'qstring', 'qdict', 'qlist', 'qfloat', 'qbool']
-    prefix QTYPE
-object foo
-object q_empty

tests/qapi-schema/doc-before-pragma.err

+tests/qapi-schema/doc-before-pragma.json:3: Documentation for 'foo' is not followed by the definition

tests/qapi-schema/doc-before-pragma.exit

-0
+1

tests/qapi-schema/doc-before-pragma.json

 # Doc comment separated from defining expression by non-defining expression
-# BUG: not rejected
 
 ##
 # @foo:

tests/qapi-schema/doc-before-pragma.out

-enum QType ['none', 'qnull', 'qint', 'qstring', 'qdict', 'qlist', 'qfloat', 'qbool']
-    prefix QTYPE
-object foo
-object q_empty

tests/qapi-schema/doc-missing-expr.err

-tests/qapi-schema/doc-missing-expr.json:3: Documention for 'bar' is not followed by the definition
+tests/qapi-schema/doc-missing-expr.json:3: Documentation for 'bar' is not followed by the definition

tests/qapi-schema/doc-no-symbol.err

-tests/qapi-schema/doc-no-symbol.json:4: Definition of 'foo' follows documentation for 'None'
+tests/qapi-schema/doc-no-symbol.json:3: Expression documentation required

tests/qapi-schema/doc-no-symbol.json

 # Documentation for expression lacks symbol
-# BUG: Error message claims it has symbol 'None'
 
 ##
 # foo: